Light emitting device

ABSTRACT

A first light emitting structure includes a first semiconductor layer, an active layer, and a second semiconductor layer. A second light emitting structure includes a third semiconductor layer, an active layer, and a fourth semiconductor layer. A first electrode and a second electrode connect to the first semiconductor layer, and the second semiconductor layer, respectively. A third electrode and a fourth electrode connect to the third semiconductor layer, and the fourth semiconductor layer, respectively. A first contact portion includes a first region connected to the first electrode and a second region making contact with a top surface of the first semiconductor layer, and a second contact portion connects to the second and third electrodes. A third contact portion includes a first region connected to the third electrode and a second region making contact with a top surface of the third semiconductor layer.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority under 35 U.S.C. §119 to KoreanPatent Application No. 10-2013-0016131 filed on Feb. 15, 2013, which ishereby incorporated by reference in its entirety.

BACKGROUND

1. Field

The embodiment relates to a light emitting device, a light emittingdevice package, and a light unit.

2. Background

A light emitting diode (LED) has been extensively used as one of lightemitting devices. The LED converts electrical signals into the form oflight such as infra-red light, visible light and ultra-violet light byusing the characteristic of a compound semiconductor.

As the light efficiency of the light emitting device is increased, thelight emitting device has been used in various fields such as displayapparatuses and lighting appliances.

The above references are incorporated by reference herein whereappropriate for appropriate teachings of additional or alternativedetails, features and/or technical background.

BRIEF DESCRIPTION OF THE DRAWINGS

The embodiments will be described in detail with reference to thefollowing drawings in which like reference numerals refer to likeelements wherein:

FIG. 1 is a view showing a light emitting device according to theembodiment.

FIG. 2 is a view showing an arrangement of a first contact portion and athird contact portion of a light emitting device shown in FIG. 1.

FIGS. 3 to 6 are sectional views showing a method of fabricating a lightemitting device according to the embodiment.

FIG. 7 is a sectional view showing a light emitting device according toanother embodiment.

FIG. 8 is a sectional view showing a light emitting device packageaccording to the embodiment.

FIG. 9 is an exploded perspective view showing a display deviceaccording to the embodiment.

FIG. 10 is a sectional view showing another example of the displaydevice according to the embodiment.

FIG. 11 is an exploded perspective view showing a lighting apparatusaccording to the embodiment.

DETAILED DESCRIPTION OF THE EMBODIMENTS

In the description of the embodiments, it will be understood that, whena layer (or film), a region, a pattern, or a structure is referred to asbeing “on” or “under” another substrate, another layer (or film),another region, another pad, or another pattern, it can be “directly” or“indirectly” over the other substrate, layer (or film), region, pad, orpattern, or one or more intervening layers may also be present. Such aposition of the layer has been described with reference to the drawings.

Hereinafter, a light emitting device, a light emitting device package, alight unit, and a method for fabricating the light emitting deviceaccording to the embodiments will be described in detail with referenceto accompanying drawings.

FIG. 1 is a view showing a light emitting device according to theembodiment and FIG. 2 is a view showing an arrangement of a firstcontact portion and a third contact portion of a light emitting deviceshown in FIG. 1.

As shown in FIGS. 1 and 2, the light emitting device according to theembodiment may include a first light emitting structure 10, a secondlight emitting structure 20, a first electrode 81, a second electrode82, a third electrode 83, a fourth electrode 84, a first contact portion91, a second contact portion 92 and a third contact portion 93.

The first light emitting structure 10 may include a first conductivefirst semiconductor layer 11, a first active layer 12, and a secondconductive second semiconductor layer 13. The first active layer 12 maybe disposed between the first conductive first semiconductor layer 11and the second conductive second semiconductor layer 13. The firstactive layer 12 may be provided under the first conductive firstsemiconductor layer 11, and the second conductive second semiconductorlayer 13 may be provided under the first active layer 12.

The first conductive first semiconductor layer 11 may include an N-typesemiconductor layer doped with N-type dopants serving as firstconductive dopants, and the second conductive second semiconductor layer13 may include a P-type semiconductor layer doped with P-type dopantsserving as second conductive dopants. In addition, the first conductivefirst semiconductor layer 11 may include a P-type semiconductor layer,and the second conductive second semiconductor layer 13 may include anN-type semiconductor layer.

For example, the first conductive first semiconductor layer 11 mayinclude an N-type semiconductor layer. The first conductive firstsemiconductor layer 11 may be realized by using a compoundsemiconductor. The first conductive first semiconductor layer 11 may berealized by using a group II-VI compound semiconductor, or a group III-Vcompound semiconductor.

For example, the first conductive first semiconductor layer 11 may berealized by using a semiconductor material having a compositionalformula of InxAlyGal-x-yN (0≦x≦1, 0≦y≦1, 0≦x+y≦y1). For example, thefirst conductive first semiconductor layer 11 may include one selectedfrom the group consisting of GaN, AlN, AlGaN, InGaN, InN, InAlGaN,AlInN, AlGaAs, GaP, GaAs, GaAsP, and AlGaInP doped with N-type dopantssuch as Si, Ge, Sn, Se, and Te.

The first active layer 12 emits light having a wavelength correspondingto the energy band gap difference according to materials constitutingthe first active layer 13 through the combination of electrons (orholes) injected through the first conductive first semiconductor layer11 and holes (or electrons) injected through the second conductivesecond semiconductor layer 13. The first active layer 12 may have one ofa single quantum well (SQW) structure, a multi-quantum well (MQW)structure, a quantum dot structure, and a quantum wire structure, butthe embodiment is not limited thereto.

The first active layer 12 may be realized by using a compoundsemiconductor. The first active layer 12 may be realized by using asemiconductor material having a compositional formula of InxAlyGal-x-yN(0≦x≦1, 0≦y≦1, 0≦x+y≦1). When the first active layer 12 has an MQWstructure, the first active layer 12 may be formed by stacking aplurality of well layers and a plurality of barrier layers. For example,the first active layer 12 may have a cycle of InGaN well layer/GaNbarrier layer.

For example, the second conductive second semiconductor layer 13 mayinclude a P-type semiconductor layer. The second conductive secondsemiconductor layer 13 may be realized by using a compoundsemiconductor. For example, the second conductive second semiconductorlayer 13 may be realized by using a group II-VI compound semiconductor,or a group II-V compound semiconductor.

For example, the second conductive second semiconductor layer 13 may berealized by using a semiconductor material having a compositionalformula of InxAlyGal-x-yN (0≦x≦1, 0≦y≦1, 0≦x+y≦1). For example, thesecond conductive second semiconductor layer 13 may include one selectedfrom the group consisting of GaN, AlN, AlGaN, InGaN, InN, InAlGaN,AlInN, AlGaAs, GaP, GaAs, GaAsP, and AlGaInP doped with P-type dopantssuch as Mg, Zn, Ca, Sr, and Ba.

Meanwhile, the first conductive first semiconductor layer 11 may includea P-type semiconductor layer and the second conductive secondsemiconductor layer 13 may include the N-type semiconductor layer. Inaddition, a semiconductor layer including an N-type or P-typesemiconductor layer may be additionally provided under the secondconductive second semiconductor layer 13. Accordingly, the first lightemitting structure 10 may have at least one of an NP junction structure,a PN junction structure, an NPN junction structure, or a PNP junctionstructure. In addition, impurities may be doped into the firstconductive first semiconductor layer 11 and the second conductive secondsemiconductor layer 13 with uniform or non-uniform doping concentration.In other words, the first light emitting structure 10 may have variousstructures, and the embodiment is not limited thereto.

In addition, a first conductive InGaN/GaN superlattice structure orInGaN/InGaN superlattice structure may be formed between the firstconductive first semiconductor layer 11 and the first active layer 12.In addition, a second conductive AlGaN layer may be formed between thesecond conductive second semiconductor layer 13 and the first activelayer 13.

The second light emitting structure 20 may include a first conductivethird semiconductor layer 21, a second active layer 22, and a secondconductive fourth semiconductor layer 23. The second active layer 22 maybe disposed between the first conductive third semiconductor layer 21and the second conductive fourth semiconductor layer 23. The secondactive layer 22 may be provided under the first conductive thirdsemiconductor layer 21, and the second conductive fourth semiconductorlayer 23 may be provided under the second active layer 22.

The first conductive third semiconductor layer 21 may include an N-typesemiconductor layer doped with N-type dopants serving as firstconductive dopants, and the second conductive fourth layer 23 mayinclude a P-type semiconductor layer doped with P-type dopants servingas second conductive dopants. In addition, the first conductive thirdsemiconductor layer 21 may include a P-type semiconductor layer, and thesecond conductive fourth semiconductor layer 23 may include an N-typesemiconductor layer.

The structure and material of the second light emitting structure 20 aresimilar to those of the first light emitting structure 10, so thedetailed description thereof will be omitted.

The light emitting device according to the embodiment may include afirst reflective layer 17. The first reflective layer may beelectrically connected to the second conductive second semiconductorlayer 13. The first reflective layer 17 may be disposed under the firstlight emitting structure 10. The first reflective layer 17 may bedisposed under the second conductive second semiconductor layer 13. Thefirst reflective layer 17 may reflect light incident thereto from thefirst light emitting structure 10 to increase the quantity of lightextracted to an outside.

The light emitting device according to the embodiment may include afirst ohmic contact layer 15 disposed between the first reflective layer17 and the second conductive second semiconductor layer 13. The firstohmic contact layer 15 may make contact with the second conductivesecond semiconductor layer 13. The first ohmic contact layer 15 may makeohmic contact with the first light emitting structure 10. The firstohmic contact layer 15 may include a region that makes ohmic-contactwith the first light emitting structure 10. The first ohmic contactlayer 15 may include a region that makes ohmic-contact with the secondconductive second semiconductor layer 13.

For example, the first ohmic contact layer 15 may include a transparentconductive oxide layer. For example, the first ohmic contact layer 15may include at least one selected from the group consisting of an ITO(Indium Tin Oxide), an IZO (Indium Zinc Oxide), an AZO (Aluminum ZincOxide), an AGZO (Aluminum Gallium Zinc Oxide), an IZTO (Indium Zinc TinOxide), an IAZO (Indium Aluminum Zinc Oxide), an IGZO (Indium GalliumZinc Oxide), an IGTO (Indium Gallium Tin Oxide), an ATO (Antimony TinOxide), a GZO (Gallium Zinc Oxide), an IZON (IZO Nitride), ZnO, IrOx,RuOx, NiO, Pt, Ag, and Ti.

The first reflective layer 17 may include a material having highreflectance. For example, the first reflective layer 17 may includemetal including at least one of Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt,Cu, Au, and Hf, and the alloy thereof. In addition, the first reflectivelayer 17 may be formed in a multi-layer of the metal or the alloythereof and a transmissive conductive material such as an ITO(Indium-Tin-Oxide), an IZO (Indium-Zinc-Oxide), an IZTO(Indium-Zinc-Tin-Oxide), an IAZO (Indium-Aluminum-Zinc-Oxide), an IGZO(Indium-Gallium-Zinc-Oxide), an IGTO (Indium-Gallium-Tin-Oxide), an AZO(Aluminum-Zinc-Oxide), or an ATO (Antimony-Tin-Oxide). For example,according to the embodiment, the first reflective layer 17 may includeat least one of Ag, Al, an Ag—Pd—Cu alloy, and an Ag—Cu alloy.

For example, the first reflective layer 17 may have a structure in whichan Ag layer and a Ni layer are alternately formed, and may includeNi/Ag/Ni or a TI layer, and a Pt layer. In addition, the first ohmiccontact layer 15 may be provided under the first reflective layer 17,and at least a portion of the first ohmic contact layer 15 may makeohmic-contact with the first light emitting structure 10 through thefirst reflective layer 17.

The light emitting device according to the embodiment may include asecond reflective layer 27. The second reflective layer 27 may beelectrically connected to the second conductive fourth semiconductorlayer 23. The second reflective layer 27 may be disposed under thesecond light emitting structure 20. The second reflective layer 27 maybe disposed under the second conductive fourth semiconductor layer 23.The second reflective layer 27 may reflect light incident thereto fromthe second light emitting structure 20 to increase the quantity of lightextracted to an outside.

The light emitting device according to the embodiment may include asecond ohmic contact layer 25 disposed between the second reflectivelayer 27 and the second conductive fourth semiconductor layer 23. Thesecond ohmic contact layer 25 may make contact with the secondconductive fourth semiconductor layer 23. The second ohmic contact layer25 may make ohmic contact with the second light emitting structure 20.The second ohmic contact layer 25 may include a region that makesohmic-contact with the second light emitting structure 20. The secondohmic contact layer 25 may include a region that makes ohmic-contactwith the second conductive fourth semiconductor layer 23.

For example, the second ohmic contact layer 25 may include a materialand a structure similar to those of the first ohmic contact layer 15. Inaddition, the second reflective layer 27 may include a material and astructure similar to those of the first reflective layer 17.

The light emitting device according to the embodiment may include afirst metal layer 35 provided under the first reflective layer 17. Thefirst metal layer 35 may include at least one of Au, Cu, Ni, Ti, Ti—W,Cr, W, Pt, V, Fe, and Mo.

The light emitting device according to the embodiment may include asecond metal layer 45 provided under the second reflective layer 27. Thesecond metal layer 45 may include at least one of Au, Cu, Ni, Ti, Ti—W,Cr, W, Pt, V, Fe, and Mo.

The first and second metal layers 35 and 45 may be formed by using thesame material or mutually different materials.

According to the embodiment, the second electrode 82 may include atleast one of the first reflective layer 17, the first ohmic contactlayer 15, and the first metal layer 35. For example, the secondelectrode 82 may include all of the first reflective layer 17, the firstmetal layer 35, and the first ohmic contact layer 15, or may include oneor two selected from the first reflective layer 17, the first metallayer 35, and the first ohmic contact layer 15.

The second electrode 82 according to the embodiment may be disposedunder the first light emitting structure 10. The second electrode 82 maybe electrically connected to the second conductive second semiconductorlayer 13.

According to the embodiment, the fourth electrode 84 may include atleast one of the second reflective layer 27, the second ohmic contactlayer 25, and the second metal layer 45. For example, the fourthelectrode 84 may include all of the second reflective layer 27, thesecond metal layer 45, and the second ohmic contact layer 25, or mayinclude one or two selected from the second reflective layer 27, thesecond metal layer 45, and the second ohmic contact layer 25.

The fourth electrode 84 according to the embodiment may be disposedunder the second light emitting structure 20. The fourth electrode 84may be electrically connected to the second conductive fourthsemiconductor layer 23.

The light emitting device according to the embodiment may include achannel layer 30 provided around a lower portion of the first lightemitting structure 10. The channel layer 30 may be provided around alower portion of the second light emitting structure 20. A first regionof the channel layer 30 may be disposed under the second conductivesecond semiconductor layer 13.

A first region of the channel layer 30 may come into contact with abottom surface of the second conductive second semiconductor layer 13. Asecond region of the channel layer 30 may be disposed under the secondconductive fourth semiconductor layer 23. The second region of thechannel layer 30 may come into contact with a bottom surface of thesecond conductive fourth semiconductor layer 23.

The first region of the channel layer 30 may be disposed between thesecond conductive second semiconductor layer 13 and the first reflectivelayer 17. The second region of the channel layer 30 may be disposedbetween the second conductive fourth semiconductor layer 23 and thesecond reflective layer 27. The first region of the channel layer 30 maybe disposed between the second conductive second semiconductor layer 13and the first ohmic contact layer 15. The second region of the channellayer 30 may be disposed between the second conductive fourthsemiconductor layer 23 and the second ohmic contact layer 25.

The channel layer 30 may be exposed at a lower peripheral portion of thefirst light emitting structure 10. The channel layer 30 may extendoutward from the sidewall of the first light emitting structure 10. Aside of the channel layer 30 may come into contact with a side of thesecond electrode 82. The side of the channel layer 30 may come intocontact with a side of the first ohmic contact layer 15. Some region ofthe channel layer 30 may be disposed on a top surface of the secondelectrode 82. Some region of the channel layer 30 may come into contactwith a top surface of the first metal layer 35.

The channel layer 30 may be exposed at a lower peripheral portion of thesecond light emitting structure 20. The channel layer 30 may extendoutward from the sidewall of the second light emitting structure 20. Aside of the channel layer 30 may come into contact with a side of thefourth electrode 84. The side of the channel layer 30 may come intocontact with a side of the second ohmic contact layer 25. Some region ofthe channel layer 30 may be disposed on a top surface of the fourthelectrode 84. Some region of the channel layer 30 may come into contactwith a top surface of the second metal layer 45.

A third region of the channel layer 30 may be disposed between the firstand second light emitting structures 10 and 20. The third region of thechannel layer 30 may be exposed between the first and second lightemitting structures 10 and 20.

The channel layer 30 may be referred to as an isolation layer. Thechannel layer 30 may serve as an etching stopper when an isolationprocess is performed with respect to the first and second light emittingstructures 10 and 20 later. In addition, the channel layer 30 mayprevent the electrical characteristic of the light emitting device frombeing degraded caused by the isolation process.

The channel layer 30 may include an insulating material. For example,the channel layer 30 may be realized by using oxide or nitride. Forexample, the channel layer 30 may include at least one selected from thegroup consisting of SiO2, SixOy, Si3N4, SixNy, SiOxNy, Al2O3, TiO2, andAlN.

The light emitting device according to the embodiment may include thefirst conduct portion 91. The first conduct portion 91 may be providedthrough the first light emitting structure 10. The first conduct portion91 may be provided through the first conductive first semiconductorlayer 11, the first active layer 12 and the second conductive secondsemiconductor layer 13.

For example, as shown in FIG. 2, a plurality of first contact portions91 may be formed in the first light emitting structure 10 according tothe embodiment. The first contact portions 91 may be disposed alongfirst through holes 55 of the first light emitting structure 10. A firstregion of the first contact portion 91 may be electrically connected tothe first electrode 81 and a second region of the first contact portion91 may make contact with a top surface of the first conductive firstsemiconductor layer 11. For instance, the first region of the firstcontact portion 91 may make contact with the third metal layer 50. Indetail, the first region of the first contact portion 91 may makecontact with the top surface of the third metal layer 50. For example,when the first light emitting structure 10 is grown into a GaNsemiconductor layer, the first contact portion 91 may make contact withan n face of the first conductive first semiconductor layer 11.

Although only one first contact portion 91 is illustrated in the lightemitting device shown in FIG. 1, the first light emitting structure 10according to the embodiment may be formed with a plurality of firstthrough holes 55 as shown in FIG. 2 and the first contact portion 91 maybe formed in each first through hole 55.

The first contact portions 91 may be spaced apart from each other on thetop surface of the first conductive first semiconductor layer 11. Sincethe first contact portions 91 are distributed on the first lightemitting structure 10, current applied to the first conductive firstsemiconductor layer 11 may be spread. Thus, the degradation of the firstconductive first semiconductor layer 11 can be prevented and thecombination efficiency of the electrons and holes in the first activelayer 12 can be improved.

According to the embodiment, the first contact portion 91 may include anohmic layer, an intermediate layer, and an upper layer. The ohmic layermay include a material selected from the group consisting of Cr, V, W,Ti, and Zn, and may make ohmic contact. The intermediate layer may berealized by using a material selected from the group consisting of Ni,Cu, and Al. For example, the upper layer may include Au. The firstcontact portion 91 may include at least one selected from the groupconsisting of Cr, V, W, Ti, Zn, Ni, Cu, Al, Au and Mo.

The light emitting device according to the embodiment may include thethird conduct portion 93. The third conduct portion 93 may be providedthrough the second light emitting structure 20. The third conductportion 93 may be provided through the first conductive thirdsemiconductor layer 21, the second active layer 22 and the secondconductive fourth semiconductor layer 23.

For example, as shown in FIG. 2, a plurality of third contact portions93 may be formed in the second light emitting structure 20 according tothe embodiment. The third contact portions 91 may be disposed alongsecond through holes 65 of the second light emitting structure 20. Afirst region of the third contact portion 93 may be electricallyconnected to the third electrode 83 and a second region of the thirdcontact portion 93 may make contact with a top surface of the firstconductive third semiconductor layer 21. For instance, the first regionof the third contact portion 93 may make contact with the thirdelectrode 83. In detail, the first region of the third contact portion93 may make contact with the top surface of the third electrode 83. Forexample, when the second light emitting structure 20 is grown into a GaNsemiconductor layer, the third contact portion 93 may make contact withan n face of the first conductive third semiconductor layer 21.

Although only one third contact portion 93 is illustrated in the lightemitting device shown in FIG. 1, the second light emitting structure 20according to the embodiment may be formed with a plurality of secondthrough holes 65 as shown in FIG. 2 and the third contact portion 93 maybe formed in each second through hole 65.

The third contact portions 93 may be spaced apart from each other on thetop surface of the first conductive third semiconductor layer 21. Sincethe third contact portions 93 are distributed on the second lightemitting structure 20, current applied to the first conductive thirdsemiconductor layer 21 may be spread. Thus, the degradation of the firstconductive third semiconductor layer 21 can be prevented and thecombination efficiency of the electrons and holes in the second activelayer 22 can be improved.

According to the embodiment, the third contact portion 93 may include anohmic layer, an intermediate layer, and an upper layer. The ohmic layermay include a material selected from the group consisting of Cr, V, W,Ti, and Zn, and may make ohmic contact. The intermediate layer may berealized by using a material selected from the group consisting of Ni,Cu, and Al. For example, the upper layer may include Au. The thirdcontact portion 93 may include at least one selected from the groupconsisting of Cr, V, W, Ti, Zn, Ni, Cu, Al, Au and Mo.

The light emitting device according to the embodiment may include thesecond conduct portion 92. The second conduct portion 92 may beelectrically connected to the second and third electrodes 82 and 83. Thesecond contact portion 92 may be disposed between the first and secondlight emitting structures 10 and 20. The second contact portion 92 maybe exposed between the first and second light emitting structures 10 and20.

One end of the second contact portion 92 may come into contact with thetop surface of the second electrode 82 and the other end of the secondcontact portion 92 may come into contact with the top surface of thethird electrode 83. The second contact portion 92 may be exposed on thethird region of the channel layer 30. The second contact portion 92 maybe spaced apart from the side of the first light emitting structure 10.The second contact portion 92 may be spaced apart from the side of thesecond light emitting structure 20.

According to the embodiment, the second contact portion 92 may includean ohmic layer, an intermediate layer, and an upper layer. The ohmiclayer may include a material selected from the group consisting of Cr,V, W, Ti, and Zn, and may make ohmic contact. The intermediate layer maybe realized by using a material selected from the group consisting ofNi, Cu, and Al. For example, the upper layer may include Au. The secondcontact portion 92 may include at least one selected from the groupconsisting of Cr, V, W, Ti, Zn, Ni, Cu, Al, Au and Mo.

Meanwhile, according to the embodiment, a plurality of the secondcontact portions 92 and the fourth contact portions 94 may be provided.

The light emitting device according to the embodiment may include athird insulating layer 33. For instance, the third insulating layer 33may be formed of oxide or nitride.

For example, the third insulating layer 33 may include at least oneselected from the group consisting of Si02, SixOy, Si3N4, SixNy, SiOxNy,Al2O3, TiO2, and AlN.

The third insulating layer 33 may be disposed in the first lightemitting structure 10. The third insulating layer 33 may be disposedaround the first contact portion 91. The third insulating layer 33 maysurround the lateral side of the first contact portion 91. The thirdinsulating layer 33 may be provided through the first conductive firstsemiconductor layer 11, the first active layer 12 and the secondconductive second semiconductor layer 13. A portion of the thirdinsulating layer 33 may extend downward from the second conductivesecond semiconductor layer 13.

A first insulating layer 31 may be disposed around the first contactportion 91. The first insulating layer 31 may be disposed around thelateral side of the first contact portion 91. The first insulating layer31 may be disposed around the third insulating layer 33. The firstinsulating layer 31 may surround the third insulating layer 33. Thefirst insulating layer 31 may be disposed under the first light emittingstructure 10. The first insulating layer 31 may be disposed under thesecond conductive second semiconductor layer 13. The first insulatinglayer 31 may come into contact with a bottom surface of the secondconductive second semiconductor layer 13.

For instance, the first insulating layer 31 may include at least oneselected from the group consisting of Si02, SixOy, Si3N4, SixNy, SiOxNy,Al2O3, TiO2, and AlN. The first and third insulating layers 31 and 33may be formed of same material or mutually different materials.

The light emitting device according to the embodiment may include afourth insulating layer 43. For instance, the fourth insulating layer 43may be formed of oxide or nitride. For example, the fourth insulatinglayer 43 may include at least one selected from the group consisting ofSi02, SixOy, Si3N4, SixNy, SiOxNy, Al2O3, TiO2, and AlN.

The fourth insulating layer 43 may be disposed in the second lightemitting structure 20. The fourth insulating layer 43 may be disposedaround the third contact portion 93. The fourth insulating layer 43 maysurround the lateral side of the third contact portion 93. The fourthinsulating layer 43 may be provided through the first conductive thirdsemiconductor layer 21, the second active layer 22 and the secondconductive fourth semiconductor layer 23. A portion of the fourthinsulating layer 43 may extend downward from the second conductivefourth semiconductor layer 23.

A second insulating layer 41 may be disposed around the third contactportion 93. The second insulating layer 41 may be disposed around thelateral side of the third contact portion 93. The second insulatinglayer 41 may be disposed around the fourth insulating layer 43. Thesecond insulating layer 41 may surround the fourth insulating layer 43.The second insulating layer 41 may be disposed under the second lightemitting structure 20. The second insulating layer 41 may be disposedunder the second conductive fourth semiconductor layer 23. The secondinsulating layer 41 may come into contact with a bottom surface of thesecond conductive fourth semiconductor layer 23.

For instance, the second insulating layer 41 may include at least oneselected from the group consisting of Si02, SixOy, Si3N4, SixNy, SiOxNy,Al2O3, TiO2, and AlN. The second and fourth insulating layers 41 and 43may be formed of same material or mutually different materials.

A fifth insulating layer 40 may be disposed between the first metallayer 35 and the first contact portion 91. The fifth insulating layer 40may be formed of oxide or nitride. For instance, the fifth insulatinglayer 40 may include at least one selected from the group consisting ofSi02, SixOy, Si3N4, SixNy, SiOxNy, Al2O3, TiO2, and AlN. The fifthinsulating layer 40 may be disposed under the first metal layer 35. Thefifth insulating layer 40 may be disposed under the third insulatinglayer 33. The fifth insulating layer 40 may be disposed under thechannel layer 30. The fifth insulating layer 40 may be disposed underthe first insulating layer 31.

The fifth insulating layer 40 may be disposed between the second metallayer 45 and the third contact portion 93. The fifth insulating layer 40may be disposed under the second metal layer 45. The fifth insulatinglayer 40 may be disposed under the fourth insulating layer 43. The fifthinsulating layer 40 may be disposed under the second insulating layer41.

The fifth insulating layer 40 may be disposed around the first contactportion 91. The fifth insulating layer 40 may be disposed around thesecond contact portion 92. The fifth insulating layer 40 may be disposedaround the third contact portion 93. The fifth insulating layer 40 maybe disposed between the first metal layer 35 and the second metal layer45.

The third metal layer 50 may be disposed under the first contact portion91. The third metal layer 50 may be electrically connected to the firstcontact portion 91. A top surface of the third metal layer 50 may comeinto contact with a bottom surface of the first contact portion 91. Thethird metal layer 50 may be disposed under the fifth insulating layer40.

The third metal layer 50 may include at least one of Cu, Ni, Ti, Ti—W,Cr, W, Pt, V, Fe, and Mo. The third metal layer 50 may serve as adiffusion barrier layer. A bonding layer 60 and a conductive supportmember 70 may be provided under the third metal layer 50.

The third metal layer 50 may prevent a material included in the bondinglayer 60 from being diffused to the first and second reflective layers17 and 27 in the process of providing the bonding layer 60. The thirdmetal layer 50 may prevent a material, such as Sn, included in thebonding layer 60 from exerting an influence on the first and secondreflective layers 17 and 27.

The bonding layer 60 includes barrier metal or bonding metal. Forexample, the bonding layer 60 may include at least one of Ti, Au, Sn,Ni, Cr, Ga, In, Bi, Cu, Ag, Nb, Pd and Ta. The conductive support member70 may support the first and second light emitting structures 10 and 20according to the embodiment while performing a heat radiation function.The bonding layer 60 may be realized in the form of a seed layer.

The conductive support member 70 may include at least one ofsemiconductor substrates (e.g., Si, Ge, GaN, GaAs, ZnO, SiC, and SiGesubstrates) implanted with Ti, Cr, Ni, Al, Pt, Au, W, Cu, Mo, Cu—W, orimpurities.

According to the embodiment, the first electrode 81 may include at leastone of the third metal layer 50, the bonding layer 60 and the conductivesupport member 70. The first electrode 81 may include all of the thirdmetal layer 50, the bonding layer 60 and the conductive support member70. In addition, the first electrode 81 may selectively include one ortwo of the third metal layer 50, the bonding layer 60 and the conductivesupport member 70.

The first electrode 81 may be disposed under the first light emittingstructure 10. The first electrode 81 may be electrically connected tothe first conductive first semiconductor layer 11. A bottom surface ofthe first electrode 81 may be disposed lower than a bottom surface ofthe second electrode 82. A top surface of the first electrode 81 may bedisposed lower than the bottom surface of the second electrode 82. Abottom surface of the first contact portion 91 may be disposed lowerthan the bottom surface of the second electrode 82. The bottom surfaceof the first contact portion 91 may be arranged on the same plane withthe top surface of the first electrode 81.

The third electrode 83 may be disposed under the third contact portion93. The third electrode 83 may be disposed under the fifth insulatinglayer 40. The third electrode 83 may be disposed between the fifthinsulating layer 40 and the third metal layer 50. The third electrode 83may be connected to the second contact portion 92. The third electrode83 may be disposed under the second light emitting structure 20. Thethird electrode 83 may be electrically connected to the first conductivethird semiconductor layer 21. The third electrode 83 may be electricallyconnected to the first conductive third semiconductor layer 21 throughthe third contact portion 93. A top surface of the first electrode 81may be arranged on the same plane with a top surface of the thirdelectrode 83.

For example, the third electrode 83 may include at least one of Cu, Ni,Ti, Ti—W, Cr, W, Pt, V, Fe, and Mo.

In addition, the light emitting device according to the embodiment mayinclude a sixth insulating layer 48 disposed between the third electrode83 and the first electrode 81. The sixth insulating layer 48 may beformed of oxide or nitride.

In addition, the light emitting device according to the embodiment mayinclude a fourth contact portion 94. The fourth contact portion 94 maybe spaced apart from the second light emitting structure 20. The fourthcontact portion 94 may be electrically connected to the fourth electrode84. The fourth contact portion 94 may be electrically connected to thefourth electrode 84 through the channel layer 30. The fourth contactportion 94 may be electrically connected to the second electrode 82. Thefourth contact portion 94 may come into contact with a top surface ofthe second electrode 82. The fourth contact portion 94 may include atleast one of Cr, V, W, Ti, Zn, Ni, Cu, Al, Au, and Mo. The fourthcontact portion 94 and the third contact portion 93 may be formed ofsame material or mutually different materials.

The roughness may be formed on the top surface of the first conductivefirst semiconductor layer 11. The roughness may be formed on the topsurface of the first conductive third semiconductor layer 21. Thus, thequantity of light extracted upward may be increased in the region wherethe roughness is formed.

According to the embodiment, power may be applied to the first andsecond light emitting structures 10 and 20 through the first electrode81 and the fourth electrode 84. For example, in the light emittingdevice according to the embodiment, the power may be applied to thefirst and second light emitting structures 10 and 20 through theconductive support member 70 of the first electrode 81 and the fourthcontact portion 94.

Accordingly, power may be supplied to the first conductive firstsemiconductor layer 11 through a scheme of attaching the conductivesupport member 70 to the bonding pad. According to the embodiment, thefourth contact portion 94 may be electrically connected to the fourthelectrode 84. Therefore, the fourth contact portion 94 is connected to apower pad through a wire bonding scheme, thereby supplying power to thesecond conductive fourth semiconductor layer 23.

As described above, according to the light emitting device of theembodiment, the power can be applied to the first and second lightemitting structures 10 and 20 through the conductive support member 70and the fourth contact portion 94. Thus, according to the embodiment,current concentration can be prevented, and the electrical reliabilitycan be improved. In addition, since a plurality of light emittingstructures are provided, a high-voltage light emitting device can beimplemented.

Meanwhile, although the embodiment illustrates the first and secondlight emitting structures 10 and 20, the number of the light emittingstructures may not be limited thereto. For instance, three or more ofthe light emitting structures may be provided. In this case, the lightemitting structures may be electrically connected to each other inseries or in a row.

In the light emitting device according to the embodiment, the firstthrough holes 55 are formed from the top surface of the first lightemitting structure 10. In addition, the second through holes 65 areformed from the top surface of the second light emitting structure 20.Thus, the manufacturing process can be simplified and the product yieldcan be improved. In addition, according to the light emitting device ofthe embodiment, an area of the electrode disposed on the top surface ofthe first and second light emitting structures 10 and 20 can be reducedso that a protective layer may be omitted from the top surface orlateral side of the first and second light emitting structures 10 and20. Therefore, the extraction efficiency of light emitted to the outsidefrom the first and second light emitting structures 10 and 20 can beimproved.

Hereinafter, a method of fabricating the light emitting device accordingto the embodiment will be described with reference to FIGS. 3 to 6.

According to the method of fabricating the light emitting device of theembodiment, as shown in FIG. 3, the first conductive semiconductor layer11 a, the active layer 12 a, and the second conductive semiconductorlayer 13 a may be formed on a substrate 5. The first conductivesemiconductor layer 11 a, the active layer 12 a, and the secondconductive semiconductor layer 13 a may be defined as the light emittingstructure 10 a.

For example, the substrate 5 may include at least one of a sapphiresubstrate (Al2O3), SiC, GaAs, GaN, ZnO, Si, GaP, InP, and Ge, but theembodiment is not limited thereto. A buffer layer may be disposedbetween the first conductive semiconductor layer 11 a and the substrate5.

The first conductive semiconductor layer 11 a may include an N-typesemiconductor layer doped with N-type dopants serving as firstconductive dopants, and the second conductive semiconductor layer 13 amay include a P-type semiconductor layer doped with P-type dopantsserving as second conductive dopants. In addition, the first conductivesemiconductor layer 11 a may include a P-type semiconductor layer, andthe second conductive semiconductor layer 13 a may include an N-typesemiconductor layer.

For example, the first conductive semiconductor layer 11 a may includean N-type semiconductor. The first conductive semiconductor layer 11 amay include a semiconductor material having a compositional formula ofInxAlyGal-x-yN (0≦x≦1, 0≦y≦1, 0≦x+y≦1). For example, the firstconductive semiconductor layer 11 a may include one selected from thegroup consisting of InAlGaN, GaN, AlGaN, AlInN, InGaN, AlN, and InN, andmay be doped with N-type dopants such as Si, Ge, Sn, Se, and Te.

The active layer 12 a emits light having a wavelength corresponding tothe energy band gap difference according to materials constituting theactive layer 12 a through the combination of electrons (or holes)injected through the first conductive semiconductor layer 11 a and holes(or electrons) injected through the second conductive semiconductorlayer 13 a. The active layer 12 a may have one of a single quantum well(SQW) structure, a multi-quantum well (MQW) structure, a quantum dotstructure, and a quantum wire structure, but the embodiment is notlimited thereto.

The active layer 12 a may be realized by using a semiconductor materialhaving a compositional formula of InxAlyGal-x-yN (0≦x≦1, 0≦y≦1,0≦x+y≦1). When the active layer 12 a has an MQW structure, the activelayer 12 a may be formed by stacking a plurality of well layers and aplurality of barrier layers. For example, the active layer 12 a may havea cycle of InGaN well layer/GaN barrier layer.

For example, the second conductive semiconductor layer 13 a may berealized by using a P type semiconductor. The second conductivesemiconductor layer 13 a may be realized by using a semiconductormaterial having a compositional formula of InxAlyGal-x-yN (0≦x≦1, 0≦y≦1,0≦x+y≦1). For example, the second conductive semiconductor layer 13 amay include one selected from the group consisting of InAlGaN, GaN,AlGaN, InGaN, AlInN, AlN, and InN, and may be doped with P-type dopantssuch as Mg, Zn, Ca, Sr, and Ba.

Meanwhile, the first conductive semiconductor layer 11 a may include aP-type semiconductor layer and the second conductive semiconductor layer13 a may include the N-type semiconductor layer. In addition, asemiconductor layer including an N-type or P-type semiconductor layermay be additionally provided on the second conductive semiconductorlayer 13 a. Accordingly, the light emitting structure 10 a may have atleast one of an NP junction structure, a PN junction structure, an NPNjunction structure, or a PNP junction structure. In addition, impuritiesmay be doped into the first conductive semiconductor layer 11 a and thesecond conductive semiconductor layer 13 a with uniform or non-uniformdoping concentration. In other words, the light emitting structure 10 amay have various structures, and the embodiment is not limited thereto.

In addition, the first conductive InGaN/GaN superlattice structure orInGaN/InGaN superlattice structure may be formed between the firstconductive semiconductor layer 11 a and the active layer 12 a. Inaddition, a second conductive AlGaN layer may be formed between thesecond conductive semiconductor layer 13 a and the active layer 12 a.

Next, as shown in FIG. 4, the channel layer 30, the first insulatinglayer 31 and the second insulating layer 41 may be formed on the lightemitting structure 10 a. The channel layer 30, the first insulatinglayer 31 and the second insulating layer 41 may be formed by using thesame material or mutually different materials. For instance, the channellayer 30, the first insulating layer 31 and the second insulating layer41 may be formed of oxide or nitride. The channel layer 30, the firstinsulating layer 31 and the second insulating layer 41 may be formed byusing at least one selected from the group consisting of Si02, SixOy,Si3N4, SixNy, SiOxNy, Al2O3, and TiO2.

Then, as shown in FIG. 4, the light emitting structure 10 a may beprovided therein with the first ohmic contact layer 15, the second ohmiccontact layer 25, the first reflective layer 17 and the secondreflective layer 27.

The first ohmic contact layer 15 may be disposed between the firstreflective layer 17 and the second conductive semiconductor layer 13 a.The first ohmic contact layer 15 may make contact with the secondconductive semiconductor layer 13 a. The second ohmic contact layer 25may be disposed between the second reflective layer 27 and the secondconductive semiconductor layer 13 a. The second ohmic contact layer 25may make contact with the second conductive semiconductor layer 13 a.

The first ohmic contact layer 15 may make ohmic-contact with the lightemitting structure 10 a. The first reflective layer 17 may beelectrically connected to the second conductive semiconductor layer 13a. The first ohmic contact layer 15 may include an ohmic-contact regionthat makes ohmic-contact with the light emitting structure 10 a. Thesecond ohmic contact layer 25 may make ohmic-contact with the lightemitting structure 10 a. The second reflective layer 27 may beelectrically connected to the second conductive semiconductor layer 13a. The second ohmic contact layer 25 may include an ohmic-contact regionthat makes ohmic-contact with the light emitting structure 10 a.

For example, the first and second ohmic contact layers 15 and 25 mayinclude a transparent conductive oxide layer. For example, the first andsecond ohmic contact layers 15 and 25 may include at least one selectedfrom the group consisting of an ITO (Indium Tin Oxide), an IZO (IndiumZinc Oxide), an AZO (Aluminum Zinc Oxide), an AGZO (Aluminum GalliumZinc Oxide), an IZTO (Indium Zinc Tin Oxide), an IAZO (Indium AluminumZinc Oxide), an IGZO (Indium Gallium Zinc Oxide), an IGTO (IndiumGallium Tin Oxide), an ATO (Antimony Tin Oxide), a GZO (Gallium ZincOxide), an IZON (IZO Nitride), ZnO, IrOx, RuOx, NiO, Pt, Ag, and Ti.

The first and second reflective layers 17 and 27 may include a materialhaving high reflectance. For example, the first and second reflectivelayers 17 and 27 may include metal including at least one of Ag, Ni, Al,Rh, Pd, Ir, Ru, Mg, Zn, Pt, Cu, Au, and Hf, and the alloy thereof.

In addition, the first and second reflective layers 17 and 27 may beformed in a multi-layer structure by using the metal or the alloythereof and a transmissive conductive material such as an ITO(Indium-Tin-Oxide), an IZO (Indium-Zinc-Oxide), an IZTO(Indium-Zinc-Tin-Oxide), an IAZO (Indium-Aluminum-Zinc-Oxide), an IGZO(Indium-Gallium-Zinc-Oxide), an IGTO (Indium-Gallium-Tin-Oxide), an AZO(Aluminum-Zinc-Oxide), or an ATO (Antimony-Tin-Oxide). For example,according to the embodiment, the first and second reflective layers 17and 27 may include at least one of Ag, Al, an Ag—Pd—Cu alloy, and anAg—Cu alloy.

For example, the first and second reflective layers 17 and 27 may have astructure in which an Ag layer and a Ni layer are alternately formed,and may include Ni/Ag/Ni or a TI layer, and a Pt layer. In addition, thefirst ohmic contact layer 15 may be provided on the first reflectivelayer 17, and at least a portion of the first ohmic contact layer 15 maymake ohmic-contact with the light emitting structure 10 a through thefirst reflective layer 17. Further, the second ohmic contact layer 25may be provided on the second reflective layer 27, and at least aportion of the second ohmic contact layer 25 may make ohmic-contact withthe light emitting structure 10 a through the second reflective layer27.

Thereafter, as shown in FIG. 5, the first metal layer 35 is formed onthe first reflective layer 17 and the second metal layer 45 is formed onthe second reflective layer 27. In addition, the fifth insulating layer40, the third electrode 83, the sixth insulating layer 48, the thirdmetal layer 50, the bonding layer 60 and the conductive support member70 are formed on the first and second metal layers 35 and 45.

The first and second metal layers 35 and 45 may include at least oneselected from the group consisting of Au, Cu, Ni, Ti, Ti—W, Cr, W, Pt,V, Fe, and Mo. According to the embodiment, the second electrode 82 mayinclude at least one of the first reflective layer 17, the first ohmiccontact layer 15, and the first metal layer 35. For example, the secondelectrode 82 may include all of the first reflective layer 17, the firstohmic contact layer 15, and the first metal layer 35 or may selectivelyinclude one or two of the first reflective layer 17, the first ohmiccontact layer 15, and the first metal layer 35. The fourth electrode 84may include at least one of the second reflective layer 27, the secondohmic contact layer 25, and the second metal layer 45. For example, thefourth electrode 84 may include all of the second reflective layer 27,the second ohmic contact layer 25, and the second metal layer 45 or mayselectively include one or two of the second reflective layer 27, thesecond ohmic contact layer 25, and the second metal layer 45.

The fifth insulating layer 40 may be formed of oxide or nitride. Forexample, the fifth insulating layer 40 may include at least one selectedfrom the group consisting of Si02, SixOy, Si3N4, SixNy, SiOxNy, Al2O3,TiO2, and AlN.

The third electrode 83 may be formed on the fifth insulating layer 40.The third electrode 83 may include at least one of Cu, Ni, Ti, Ti—W, Cr,W, Pt, V, Fe, and Mo. The third electrode 83 may serve as a diffusionbarrier layer.

The sixth insulating layer 48 may be formed on the third electrode 83.For instance, the sixth insulating layer 48 may include at least oneselected from the group consisting of Si02, SixOy, Si3N4, SixNy, SiOxNy,Al2O3, TiO2, and AlN.

The third metal layer 50 may be disposed on the sixth insulating layer48. The third metal layer 50 may include at least one of Cu, Ni, Ti,Ti—W, Cr, W, Pt, V, Fe, and Mo. The third metal layer 50 may serve as adiffusion barrier layer. The bonding layer 60 and the conductive supportmember 70 may be provided on the third metal layer 50.

The third metal layer 50 may prevent a material included in the bondinglayer 60 from being diffused to the first and second reflective layers17 and 27 in the process of providing the bonding layer 60. The thirdmetal layer 50 may prevent a material, such as Sn, included in thebonding layer 60 from exerting an influence on the first and secondreflective layers 17 and 27.

The bonding layer 60 includes barrier metal or bonding metal. Forexample, the bonding layer 60 may include at least one of Ti, Au, Sn,Ni, Cr, Ga, In, Bi, Cu, Ag, Nb, Pd and Ta. The conductive support member70 may support the light emitting structure 10 a according to theembodiment while performing a heat radiation function. The bonding layer60 may be realized in the form of a seed layer.

The conductive support member 70 may include at least one ofsemiconductor substrates (e.g., Si, Ge, GaN, GaAs, ZnO, SiC, and SiGesubstrates) implanted with Ti, Cr, Ni, Al, Pt, Au, W, Cu, Mo, Cu—W, orimpurities.

According to the embodiment, the first electrode 81 may include at leastone of the third metal layer 50, the bonding layer 60 and the conductivesupport member 70. The first electrode 81 may include all of the thirdmetal layer 50, the bonding layer 60 and the conductive support member70. In addition, the first electrode 81 may selectively include one ortwo of the third metal layer 50, the bonding layer 60 and the conductivesupport member 70.

Next, the substrate 5 is removed from the first conductive semiconductorlayer 11. According to one example, the substrate 5 may be removedthrough a laser lift off (LLO) process. The LLO process is a process todelaminate the substrate 5 from the first conductive semiconductor layer11 a by irradiating a laser to the bottom surface of the substrate 5.

In addition, as shown in FIG. 6, the lateral side of the light emittingstructure 10 a is etched through an isolation etching process to exposea portion of the channel layer 30. The isolation etching process may beperformed through a dry etching process such as an inductively coupledplasma (ICP), but the embodiment is not limited thereto. The first andsecond light emitting structures 10 and 20 may be provided through theisolation etching process.

The first light emitting structure 10 may include the first conductivefirst semiconductor layer 11, the first active layer 12 and the secondconductive second semiconductor layer 13. The second light emittingstructure 20 may include the first conductive third semiconductor layer21, the second active layer 22 and the second conductive fourthsemiconductor layer 23.

The roughness may be formed on the top surface of the first and secondlight emitting structures 10 and 20. Accordingly, a light extractionpattern may be provided on the top surface of the first and second lightemitting structures 10 and 20. A concave-convex pattern may be providedon the top surface of the first and second light emitting structures 10and 20. For example, the light extraction pattern provided on the firstand second light emitting structures 10 and 20 may be provided through aPEC (photo electro chemical) etching process. Therefore, according tothe embodiment, the external light extraction effect can be increased.

Next, as shown in FIG. 6, the third insulating layer 33, the fourthinsulating layer 43, the first contact portion 91, the second contactportion 92, the third contact portion 93 and the fourth contact portion94 may be formed.

The third insulating layer 33 may be provided through the first lightemitting structure 10. The third insulating layer 33 may come intocontact with the fifth insulating layer 40 by passing through the firstlight emitting structure 10. The third insulating layer 33 may come intocontact with a lateral side of the first insulating layer 31 by passingthrough the first light emitting structure 10. For instance, the thirdinsulating layer 33 may be formed of oxide or nitride.

The fourth insulating layer 43 may be provided through the second lightemitting structure 20. The fourth insulating layer 43 may come intocontact with the fifth insulating layer 40 by passing through the secondlight emitting structure 20. The fourth insulating layer 43 may comeinto contact with a lateral side of the second insulating layer 41 bypassing through the second light emitting structure 20. For instance,the fourth insulating layer 43 may be formed of oxide or nitride.

The light emitting device according to the embodiment may include thefirst conduct portion 91. The first conduct portion 91 may be providedthrough the first light emitting structure 10. The first conduct portion91 may be provided through the first conductive first semiconductorlayer 11, the first active layer 12 and the second conductive secondsemiconductor layer 13.

For example, as shown in FIG. 2, a plurality of first contact portions91 may be formed in the first light emitting structure 10 according tothe embodiment. The first contact portions 91 may be disposed alongfirst through holes 55 of the first light emitting structure 10. A firstregion of the first contact portion 91 may be electrically connected tothe first electrode 81 and a second region of the first contact portion91 may make contact with a top surface of the first conductive firstsemiconductor layer 11. For instance, the first region of the firstcontact portion 91 may make contact with the third metal layer 50. Indetail, the first region of the first contact portion 91 may makecontact with the top surface of the third metal layer 50. For example,when the first light emitting structure 10 is grown into a GaNsemiconductor layer, the first contact portion 91 may make contact withan n face of the first conductive first semiconductor layer 11.

Although only one first contact portion 91 is illustrated in the lightemitting device shown in FIG. 6, the first light emitting structure 10according to the embodiment may be formed with a plurality of firstthrough holes 55 as shown in FIG. 2 and the first contact portion 91 maybe formed in each first through hole 55.

The first contact portions 91 may be spaced apart from each other on thetop surface of the first conductive first semiconductor layer 11. Sincethe first contact portions 91 are distributed on the first lightemitting structure 10, current applied to the first conductive firstsemiconductor layer 11 may be spread. Thus, the degradation of the firstconductive first semiconductor layer 11 can be prevented and thecombination efficiency of the electrons and holes in the first activelayer 12 can be improved.

According to the embodiment, the first contact portion 91 may include anohmic layer, an intermediate layer, and an upper layer. The ohmic layermay include a material selected from the group consisting of Cr, V, W,Ti, and Zn, and may make ohmic contact. The intermediate layer may berealized by using a material selected from the group consisting of Ni,Cu, and Al. For example, the upper layer may include Au. The firstcontact portion 91 may include at least one selected from the groupconsisting of Cr, V, W, Ti, Zn, Ni, Cu, Al, Au and Mo.

The light emitting device according to the embodiment may include thethird conduct portion 93. The third conduct portion 93 may be providedthrough the second light emitting structure 20. The third conductportion 93 may be provided through the first conductive thirdsemiconductor layer 21, the second active layer 22 and the secondconductive fourth semiconductor layer 23.

For example, as shown in FIG. 2, a plurality of third contact portions93 may be formed in the second light emitting structure 20 according tothe embodiment. The third contact portions 91 may be disposed alongsecond through holes 65 of the second light emitting structure 20. Afirst region of the third contact portion 93 may be electricallyconnected to the third electrode 83 and a second region of the thirdcontact portion 93 may make contact with a top surface of the firstconductive third semiconductor layer 21. For instance, the first regionof the third contact portion 93 may make contact with the thirdelectrode 83. In detail, the first region of the third contact portion93 may make contact with the top surface of the third electrode 83. Forexample, when the second light emitting structure 20 is grown into a GaNsemiconductor layer, the third contact portion 93 may make contact withan n face of the first conductive third semiconductor layer 21.

Although only one third contact portion 93 is illustrated in the lightemitting device shown in FIG. 6, the second light emitting structure 20according to the embodiment may be formed with a plurality of secondthrough holes 65 as shown in FIG. 2 and the third contact portion 93 maybe formed in each second through hole 65.

The third contact portions 93 may be spaced apart from each other on thetop surface of the first conductive third semiconductor layer 21. Sincethe third contact portions 93 are distributed on the second lightemitting structure 20, current applied to the first conductive thirdsemiconductor layer 21 may be spread. Thus, the degradation of the firstconductive third semiconductor layer 21 can be prevented and thecombination efficiency of the electrons and holes in the second activelayer 22 can be improved.

According to the embodiment, the third contact portion 93 may include anohmic layer, an intermediate layer, and an upper layer. The ohmic layermay include a material selected from the group consisting of Cr, V, W,Ti, and Zn, and may make ohmic contact. The intermediate layer may berealized by using a material selected from the group consisting of Ni,Cu, and Al. For example, the upper layer may include Au. The thirdcontact portion 93 may include at least one selected from the groupconsisting of Cr, V, W, Ti, Zn, Ni, Cu, Al, Au and Mo.

The light emitting device according to the embodiment may include thesecond conduct portion 92. The second conduct portion 92 may beelectrically connected to the second and third electrodes 82 and 83. Thesecond contact portion 92 may be disposed between the first and secondlight emitting structures 10 and 20. The second contact portion 92 maybe exposed between the first and second light emitting structures 10 and20.

One end of the second contact portion 92 may come into contact with thetop surface of the second electrode 82 and the other end of the secondcontact portion 92 may come into contact with the top surface of thethird electrode 83. The second contact portion 92 may be exposed on thechannel layer 30. The second contact portion 92 may be spaced apart fromthe side of the first light emitting structure 10. The second contactportion 92 may be spaced apart from the side of the second lightemitting structure 20.

According to the embodiment, the second contact portion 92 may includean ohmic layer, an intermediate layer, and an upper layer. The ohmiclayer may include a material selected from the group consisting of Cr,V, W, Ti, and Zn, and may make ohmic contact. The intermediate layer maybe realized by using a material selected from the group consisting ofNi, Cu, and Al. For example, the upper layer may include Au. The secondcontact portion 92 may include at least one selected from the groupconsisting of Cr, V, W, Ti, Zn, Ni, Cu, Al, Au and Mo.

In addition, the light emitting device according to the embodiment mayinclude a fourth contact portion 94. The fourth contact portion 94 maybe spaced apart from the second light emitting structure 20. The fourthcontact portion 94 may be electrically connected to the fourth electrode84. The fourth contact portion 94 may be electrically connected to thefourth electrode 84 through the channel layer 30. The fourth contactportion 94 may be electrically connected to the second electrode 82. Thefourth contact portion 94 may come into contact with a top surface ofthe second electrode 82. The fourth contact portion 94 may include atleast one of Cr, V, W, Ti, Zn, Ni, Cu, Al, Au, and Mo. The fourthcontact portion 94 and the third contact portion 93 may be formed ofsame material or mutually different materials.

Meanwhile, according to the embodiment, a plurality of second contactportions 92 and fourth contact portions 94 may be provided. In addition,the manufacturing process described above is illustrative purpose onlyand may be variously modified.

According to the embodiment, power may be applied to the first andsecond light emitting structures 10 and 20 through the first electrode81 and the fourth electrode 84. For example, in the light emittingdevice according to the embodiment, the power may be applied to thefirst and second light emitting structures 10 and 20 through theconductive support member 70 of the first electrode 81 and the fourthcontact portion 94.

Accordingly, power may be supplied to the first conductive firstsemiconductor layer 11 through a scheme of attaching the conductivesupport member 70 to the bonding pad. According to the embodiment, thefourth contact portion 94 may be electrically connected to the fourthelectrode 84. Therefore, the fourth contact portion 94 is connected to apower pad through a wire bonding scheme, thereby supplying power to thesecond conductive fourth semiconductor layer 23.

As described above, according to the light emitting device of theembodiment, the power can be applied to the first and second lightemitting structures 10 and 20 through the conductive support member 70and the fourth contact portion 94. Thus, according to the embodiment,current concentration can be prevented, and the electrical reliabilitycan be improved. In addition, since a plurality of light emittingstructures are provided, a high-voltage light emitting device can beimplemented.

Meanwhile, although the embodiment illustrates the first and secondlight emitting structures 10 and 20, the number of the light emittingstructures may not be limited thereto. For instance, three or more ofthe light emitting structures may be provided. In this case, the lightemitting structures may be electrically connected to each other inseries or in a row.

In the light emitting device according to the embodiment, the firstthrough holes 55 are formed from the top surface of the first lightemitting structure 10. In addition, the second through holes 65 areformed from the top surface of the second light emitting structure 20.Thus, the manufacturing process can be simplified and the product yieldcan be improved. In addition, according to the light emitting device ofthe embodiment, an area of the electrode disposed on the top surface ofthe first and second light emitting structures 10 and 20 can be reducedso that a protective layer may be omitted from the top surface orlateral side of the first and second light emitting structures 10 and20. Therefore, the extraction efficiency of light emitted to the outsidefrom the first and second light emitting structures 10 and 20 can beimproved.

FIG. 7 is a sectional view showing another example of a light emittingdevice according to the embodiment. In the following description aboutthe light emitting device shown in FIG. 7, components and structures thesame as those described with reference to FIGS. 1 and 2 will not befurther described in order to avoid redundancy.

According to the light emitting device of the embodiment, a first ohmicreflective layer 19 may be provided under the first light emittingstructure 10. The first ohmic reflective layer 19 may be realized suchthat the first ohmic reflective layer 19 may serve as both of the firstreflective layer 17 and the first ohmic contact layer 15. Accordingly,the first ohmic reflective layer 19 may make ohmic-contact with thesecond conductive second semiconductor layer 13, and reflect the lightincident thereto from the first light emitting structure 10.

In this case, the first ohmic reflective layer 19 may include multiplelayers. For example, the first ohmic reflective layer 19 may have astructure in which an Ag layer and a Ni layer are alternately formed, ormay include a Ni/Ag/Ni layer, a Ti layer, or a Pt layer.

According to the light emitting device of the embodiment, the conductivesupport member 70 provided under the first ohmic reflective layer 19 maybe electrically connected to the first conductive first semiconductorlayer 11 provided on the first ohmic reflective layer 19.

The second electrode 82 according to the embodiment may include at leastone of the first ohmic reflective layer 19 and the first metal layer 35.In the light emitting device according to the embodiment, the conductivesupport member 70 provided under the second electrode 82 may beelectrically connected to the first conductive first semiconductor layer11 provided on the second electrode 82 through the first contact portion91.

According to the light emitting device of the embodiment, a second ohmicreflective layer 29 may be provided under the second light emittingstructure 20. The second ohmic reflective layer 29 may be realized suchthat the second ohmic reflective layer 29 may serve as both of thesecond reflective layer 27 and the second ohmic contact layer 25.Accordingly, the second ohmic reflective layer 29 may make ohmic-contactwith the second conductive fourth semiconductor layer 23, and reflectthe light incident thereto from the second light emitting structure 20.

In this case, the second ohmic reflective layer 29 may include multiplelayers. For example, the second ohmic reflective layer 29 may have astructure in which an Ag layer and a Ni layer are alternately formed, ormay include a Ni/Ag/Ni layer, a Ti layer, or a Pt layer.

The fourth electrode 84 according to the embodiment may include at leastone of the second ohmic reflective layer 29 and the second metal layer45. The fourth electrode 84 may be electrically connected to the firstconductive third semiconductor layer 21 through the third contactportion 93.

The light emitting device according to the embodiment may include thefirst conduct portion 91. The first conduct portion 91 may be providedthrough the first light emitting structure 10. The first conduct portion91 may be provided through the first conductive first semiconductorlayer 11, the first active layer 12 and the second conductive secondsemiconductor layer 13.

For example, as shown in FIG. 2, a plurality of first contact portions91 may be formed in the first light emitting structure 10 according tothe embodiment. The first contact portions 91 may be disposed alongfirst through holes 55 of the first light emitting structure 10. A firstregion of the first contact portion 91 may be electrically connected tothe first electrode 81 and a second region of the first contact portion91 may make contact with a top surface of the first conductive firstsemiconductor layer 11. For instance, the first region of the firstcontact portion 91 may make contact with the third metal layer 50. Indetail, the first region of the first contact portion 91 may makecontact with the top surface of the third metal layer 50. For example,when the first light emitting structure 10 is grown into a GaNsemiconductor layer, the first contact portion 91 may make contact withan n face of the first conductive first semiconductor layer 11.

Although only one first contact portion 91 is illustrated in the lightemitting device shown in FIG. 7, the first light emitting structure 10according to the embodiment may be formed with a plurality of firstthrough holes 55 as shown in FIG. 2 and the first contact portion 91 maybe formed in each first through hole 55.

The first contact portions 91 may be spaced apart from each other on thetop surface of the first conductive first semiconductor layer 11. Sincethe first contact portions 91 are distributed on the first lightemitting structure 10, current applied to the first conductive firstsemiconductor layer 11 may be spread. Thus, the degradation of the firstconductive first semiconductor layer 11 can be prevented and thecombination efficiency of the electrons and holes in the first activelayer 12 can be improved.

According to the embodiment, the first contact portion 91 may include anohmic layer, an intermediate layer, and an upper layer. The ohmic layermay include a material selected from the group consisting of Cr, V, W,Ti, and Zn, and may make ohmic contact. The intermediate layer may berealized by using a material selected from the group consisting of Ni,Cu, and Al. For example, the upper layer may include Au. The firstcontact portion 91 may include at least one selected from the groupconsisting of Cr, V, W, Ti, Zn, Ni, Cu, Al, Au and Mo.

The light emitting device according to the embodiment may include thethird conduct portion 93. The third conduct portion 93 may be providedthrough the second light emitting structure 20. The third conductportion 93 may be provided through the first conductive thirdsemiconductor layer 21, the second active layer 22 and the secondconductive fourth semiconductor layer 23.

For example, as shown in FIG. 2, a plurality of third contact portions93 may be formed in the second light emitting structure 20 according tothe embodiment. The third contact portions 91 may be disposed alongsecond through holes 65 of the second light emitting structure 20. Afirst region of the third contact portion 93 may be electricallyconnected to the third electrode 83 and a second region of the thirdcontact portion 93 may make contact with a top surface of the firstconductive third semiconductor layer 21. For instance, the first regionof the third contact portion 93 may make contact with the thirdelectrode 83. In detail, the first region of the third contact portion93 may make contact with the top surface of the third electrode 83. Forexample, when the second light emitting structure 20 is grown into a GaNsemiconductor layer, the third contact portion 93 may make contact withan n face of the first conductive third semiconductor layer 21.

Although only one third contact portion 93 is illustrated in the lightemitting device shown in FIG. 7, the second light emitting structure 20according to the embodiment may be formed with a plurality of secondthrough holes 65 as shown in FIG. 2 and the third contact portion 93 maybe formed in each second through hole 65.

The third contact portions 93 may be spaced apart from each other on thetop surface of the first conductive third semiconductor layer 21. Sincethe third contact portions 93 are distributed on the second lightemitting structure 20, current applied to the first conductive thirdsemiconductor layer 21 may be spread. Thus, the degradation of the firstconductive third semiconductor layer 21 can be prevented and thecombination efficiency of the electrons and holes in the second activelayer 22 can be improved.

According to the embodiment, the third contact portion 93 may include anohmic layer, an intermediate layer, and an upper layer. The ohmic layermay include a material selected from the group consisting of Cr, V, W,Ti, and Zn, and may make ohmic contact. The intermediate layer may berealized by using a material selected from the group consisting of Ni,Cu, and Al. For example, the upper layer may include Au. The thirdcontact portion 93 may include at least one selected from the groupconsisting of Cr, V, W, Ti, Zn, Ni, Cu, Al, Au and Mo.

The light emitting device according to the embodiment may include thesecond conduct portion 92. The second conduct portion 92 may beelectrically connected to the second and third electrodes 82 and 83. Thesecond contact portion 92 may be disposed between the first and secondlight emitting structures 10 and 20. The second contact portion 92 maybe exposed between the first and second light emitting structures 10 and20.

One end of the second contact portion 92 may come into contact with thetop surface of the second electrode 82 and the other end of the secondcontact portion 92 may come into contact with the top surface of thethird electrode 83. The second contact portion 92 may be exposed on thethird region of the channel layer 30. The second contact portion 92 maybe spaced apart from the side of the first light emitting structure 10.The second contact portion 92 may be spaced apart from the side of thesecond light emitting structure 20.

According to the embodiment, the second contact portion 92 may includean ohmic layer, an intermediate layer, and an upper layer. The ohmiclayer may include a material selected from the group consisting of Cr,V, W, Ti, and Zn, and may make ohmic contact. The intermediate layer maybe realized by using a material selected from the group consisting ofNi, Cu, and Al. For example, the upper layer may include Au. The secondcontact portion 92 may include at least one selected from the groupconsisting of Cr, V, W, Ti, Zn, Ni, Cu, Al, Au and Mo.

In addition, the light emitting device according to the embodiment mayinclude a fourth contact portion 94. The fourth contact portion 94 maybe spaced apart from the second light emitting structure 20. The fourthcontact portion 94 may be electrically connected to the fourth electrode84. The fourth contact portion 94 may be electrically connected to thefourth electrode 84 through the channel layer 30. The fourth contactportion 94 may be electrically connected to the second electrode 82. Thefourth contact portion 94 may come into contact with a top surface ofthe second electrode 82. The fourth contact portion 94 may include atleast one of Cr, V, W, Ti, Zn, Ni, Cu, Al, Au, and Mo. The fourthcontact portion 94 and the third contact portion 93 may be formed ofsame material or mutually different materials.

Meanwhile, according to the embodiment, a plurality of second contactportions 92 and fourth contact portions 94 may be provided.

According to the embodiment, power may be applied to the first andsecond light emitting structures 10 and 20 through the first electrode81 and the fourth electrode 84. For example, in the light emittingdevice according to the embodiment, the power may be applied to thefirst and second light emitting structures 10 and 20 through theconductive support member 70 of the first electrode 81 and the fourthcontact portion 94.

Accordingly, power may be supplied to the first conductive firstsemiconductor layer 11 through a scheme of attaching the conductivesupport member 70 to the bonding pad. According to the embodiment, thefourth contact portion 94 may be electrically connected to the fourthelectrode 84. Therefore, the fourth contact portion 94 is connected to apower pad through a wire bonding scheme, thereby supplying power to thesecond conductive fourth semiconductor layer 23.

As described above, according to the light emitting device of theembodiment, the power can be applied to the first and second lightemitting structures 10 and 20 through the conductive support member 70and the fourth contact portion 94. Thus, according to the embodiment,current concentration can be prevented, and the electrical reliabilitycan be improved. In addition, since a plurality of light emittingstructures are provided, a high-voltage light emitting device can beimplemented.

Meanwhile, although the embodiment illustrates the first and secondlight emitting structures 10 and 20, the number of the light emittingstructures may not be limited thereto. For instance, three or more ofthe light emitting structures may be provided. In this case, the lightemitting structures may be electrically connected to each other inseries or in a row.

In the light emitting device according to the embodiment, the firstthrough holes 55 are formed from the top surface of the first lightemitting structure 10. In addition, the second through holes 65 areformed from the top surface of the second light emitting structure 20.Thus, the manufacturing process can be simplified and the product yieldcan be improved. In addition, according to the light emitting device ofthe embodiment, an area of the electrode disposed on the top surface ofthe first and second light emitting structures 10 and 20 can be reducedso that a protective layer may be omitted from the top surface orlateral side of the first and second light emitting structures 10 and20. Therefore, the extraction efficiency of light emitted to the outsidefrom the first and second light emitting structures 10 and 20 can beimproved.

FIG. 8 is a sectional view showing a light emitting device package towhich the light emitting device according to the embodiment is applied.

Referring to FIG. 15, the light emitting device package according to theembodiment may include a body 120, first and second lead electrodes 131and 132 formed on the body 120, a light emitting device 100 provided onthe body 120 and electrically connected to the first and second leadelectrodes 131 and 132 and a molding member 140 that surrounds the lightemitting device 100.

The body 120 may include silicon, synthetic resin or metallic material,and an inclined surface may be formed in the vicinity of the lightemitting device 100.

The first and second lead electrodes 131 and 132 are electricallyisolated from each other to supply power to the light emitting device100. The first and second lead electrode 131 and 132 can improve thelight efficiency by reflecting the light emitted from the light emittingdevice 100. Further, the first and second lead electrodes 131 and 132dissipate heat generated from the light emitting device 100 to theoutside.

The light emitting device 100 can be installed on the body 120 or thefirst or second lead electrode 131 or 132.

The light emitting device 100 may be electrically connected to the firstand second lead electrodes 131 and 132 through one of a wire scheme, aflip-chip scheme, and a die-bonding scheme.

The molding member 140 may surround the light emitting device 100 toprotect the light emitting device 100. In addition, the molding member140 may include phosphors to change the wavelength of the light emittedfrom the light emitting device 100.

A plurality of light emitting device or light emitting device packagesaccording to the embodiment may be arrayed on a board, and an opticalmember including a lens, a light guide plate, a prism sheet, or adiffusion sheet may be provided on the optical path of the light emittedfrom the light emitting device package. The light emitting devicepackage, the board, and the optical member may serve as a light unit.The light unit is realized in a top view type or a side view type andvariously provided in display devices of a portable terminal and alaptop computer or a lighting apparatus and an indicator apparatus. Inaddition, a lighting apparatus according to another embodiment caninclude a light emitting device, or a light emitting device packageaccording to the embodiment. For example, the lighting apparatus mayinclude a lamp, a signal lamp, an electric sign board and a headlight ofa vehicle.

The light emitting device according to the embodiment may be applied tothe light unit. The light unit has a structure in which a plurality oflight emitting devices are arrayed. The light unit may include a displaydevice as shown in FIGS. 9 and 10 and the lighting apparatus as shown inFIG. 11.

Referring to FIG. 9, a display device 1000 according to the embodimentincludes a light guide plate 1041, a light emitting module 1031 forsupplying the light to the light guide plate 1041, a reflective member1022 provided below the light guide plate 1041, an optical sheet 1051provided above the light guide plate 1041, a display panel 1061 providedabove the optical sheet 1051, and a bottom cover 1011 for receiving thelight guide plate 1041, the light emitting module 1031, and thereflective member 1022. However, the embodiment is not limited to theabove structure.

The bottom cover 1011, the reflective member 1022, the light guide plate1041 and the optical sheet 1051 may constitute a light unit 1050.

The light guide plate 1041 diffuses the light to provide surface light.The light guide plate 1041 may include transparent material. Forexample, the light guide plate 1041 may include one of acryl-basedresin, such as PMMA (polymethyl methacrylate), PET (polyethyleneterephthalate), PC (polycarbonate), COC (cyclic olefin copolymer) andPEN (polyethylene naphthalate) resin.

The light emitting module 1031 supplies the light to at least one sideof the light guide plate 1041. The light emitting module 1031 serves asthe light source of the display device.

At least one light emitting module 1031 is provided to directly orindirectly supply the light from one side of the light guide plate 1041.The light emitting module 1031 may include a board 1033 and lightemitting devices 100 or the light emitting device package 200 accordingto the embodiment described above. The light emitting packages 200 maybe arrayed on the board 1033 while being spaced apart from each other atthe predetermined interval.

The board 1033 may be a printed circuit board (PCB) including a circuitpattern. In addition, the board 1033 may also include a metal core PCB(MCPCB) or a flexible PCB (FPCB) as well as the PCB, but the embodimentis not limited thereto. If the light emitting device packages 200 areinstalled on the lateral side of the bottom cover 1011 or on a heatdissipation plate, the board 1033 may be omitted. The heat dissipationplate may partially make contact with the top surface of the bottomcover 1011.

In addition, the light emitting device packages 200 are installed suchthat light exit surfaces of the light emitting device packages 200 arespaced apart from the light guide plate 1041 at a predetermineddistance, but the embodiment is not limited thereto. The light emittingdevice packages 200 may directly or indirectly supply the light to alight incident part, which is one side of the light guide plate 1041,but the embodiment is not limited thereto.

The reflective member 1022 may be disposed below the light guide plate1041. The reflective member 1022 reflects the light, which travelsdownward through the bottom surface of the light guide plate 1041,upward, thereby improving the brightness of the light unit 1050. Forexample, the reflective member 1022 may include PET, PC or PVC resin,but the embodiment is not limited thereto. The reflective member 1022may serve as the top surface of the bottom cover 1011, but theembodiment is not limited thereto.

The bottom cover 1011 may receive the light guide plate 1041, the lightemitting module 1031, and the reflective member 1022 therein. To thisend, the bottom cover 1011 has a receiving section 1012 having a boxshape with an opened top surface, but the embodiment is not limitedthereto. The bottom cover 1011 can be coupled with the top cover (notshown), but the embodiment is not limited thereto.

The bottom cover 1011 can be manufactured through a press process or anextrusion process by using metallic material or resin material. Inaddition, the bottom cover 1011 may include metal or non-metallicmaterial having superior thermal conductivity, but the embodiment is notlimited thereto.

The display panel 1061, for example, is an LCD panel including first andsecond transparent substrates, which are opposite to each other, and aliquid crystal layer disposed between the first and second substrates. Apolarizing plate can be attached to at least one surface of the displaypanel 1061, but the embodiment is not limited thereto. The display panel1061 displays information by using light passing through the opticalsheet 1051. The display device 1000 can be applied to various portableterminals, monitors of notebook computers and laptop computers, andtelevisions.

The optical sheet 1051 is disposed between the display panel 1061 andthe light guide plate 1041 and includes at least one transmissive sheet.For example, the optical sheet 1051 includes at least one of a diffusionsheet, horizontal and vertical prism sheets, and a brightness enhancedsheet. The diffusion sheet diffuses the incident light, the horizontaland/or vertical prism sheet concentrates the incident light onto adisplay region, and the brightness enhanced sheet improves thebrightness by reusing the light to be lost. In addition, a protectivesheet can be provided on the display panel 1061, but the embodiment isnot limited thereto.

The light guide plate 1041 and the optical sheet 1051 can be provided onthe optical path of the light emitting module 1031 as optical members,but the embodiment is not limited thereto.

FIG. 10 is a sectional view showing another example of a display deviceaccording to the embodiment.

Referring to FIG. 10, the display device 1100 includes a bottom cover1152, a board 1020 on which the light emitting devices 100 are arrayed,an optical member 1154, and a display panel 1155. The board 1020 and thelight emitting device packages 200 may constitute a light emittingmodule 1060. In addition, the bottom cover 1152, at least one lightemitting module 1060, and the optical member 1154 may constitute thelight unit. The bottom cover 1152 can be provided therein with areceiving section 1153, but the embodiment is not limited thereto.

In this case, the optical member 1154 may include at least one of alens, a light guide plate, a diffusion sheet, horizontal and verticalprism sheets, and a brightness enhanced sheet. The light guide plate mayinclude PC or PMMA (Poly methyl methacrylate). The light guide plate canbe omitted. The diffusion sheet diffuses the incident light, thehorizontal and vertical prism sheets concentrate the incident light ontoa display region, and the brightness enhanced sheet improves thebrightness by reusing the light to be lost.

The optical member 1154 is disposed above the light emitting module 1060in order to convert the light emitted from the light emitting module1060 into the surface light. In addition, the optical member 1154 maydiffuse or collect the light.

FIG. 11 is a perspective view showing a lighting apparatus according tothe embodiment.

Referring to FIG. 11, the lighting apparatus according to the embodimentmay include a cover 2100, a light source module 2200, a radiator 2400, apower supply part 2600, an inner case 2700, and a socket 2800. Thelighting apparatus according to the embodiment may further include atleast one of a member 2300 and a holder 2500. The light source module2200 may include the light emitting device package according to theembodiment.

For example, the cover 2100 may have a blub shape or a hemisphericshape. The cover 2100 may have a hollow structure which is partiallyopen. The cover 2100 may be optically coupled with the light sourcemodule 2200. For example, the cover 2100 may diffuse, scatter, or excitelight provided from the light source module 2200. The cover 2100 may bean optical member. The cover 2100 may be coupled with the radiator 2400.The cover 2100 may include a coupling part which is coupled with theradiator 2400.

The cover 2100 may include an inner surface coated with a milk-whitepigment. The milk-white pigment may include a diffusion material todiffuse light. The roughness of the inner surface of the cover 2100 maybe greater than the roughness of the outer surface of the cover 2100.The surface roughness is provided for the purpose of sufficientlyscattering and diffusing the light from the light source module 2200.

The cover 2100 may include glass, plastic, polypropylene (PP),polyethylene (PE) or polycarbonate (PC). The polycarbonate (PC) has thesuperior light resistance, heat resistance and strength among the abovematerials. The cover 2100 may be transparent so that a user may view thelight source module 2200 from the outside, or may be opaque. The cover2100 may be provided through a blow molding scheme.

The light source module 220 may be disposed at one surface of theradiator 2400. Accordingly, the heat from the light source module 220 istransferred to the radiator 2400. The light source module 2200 mayinclude a light source 2210, a connection plate 2230, and a connector2250.

The member 2300 is disposed on a top surface of the radiator 2400, andincludes guide grooves 2310 into which a plurality of light sources 2210and the connector 2250 are inserted. The guide grooves 2310 correspondto a board of the light source 2210 and the connector 2250.

A surface of the member 2300 may be coated with a light reflectivematerial. For example, the surface of the member 2300 may be coated withwhite pigment. The member 2300 reflects again light, which is reflectedby the inner surface of the cover 2100 and is returned to the directionof the light source module 2200, to the direction of the cover 2100.Accordingly, the light efficiency of the lighting apparatus according tothe embodiment may be improved.

For example, the member 2300 may include an insulating material. Theconnection plate 2230 of the light source module 2200 may include anelectrically conductive material. Accordingly, the radiator 2400 may beelectrically connected to the connection plate 2230. The member 2300 maybe formed by an insulating material, thereby preventing the connectionplate 2230 from being electrically shorted with the radiator 2400. Theradiator 2400 receives heat from the light source module 2200 and thepower supply part 2600 and dissipates the heat.

The holder 2500 covers a receiving groove 2719 of an insulating part2710 of an inner case 2700. Accordingly, the power supply part 2600received in the insulating part 2710 of the inner case 2700 is sealed.The holder 2500 includes a guide protrusion 2510. The guide protrusion2510 has a hole and a protrusion of the power supply part 2600 extendsby passing through the hole.

The power supply part 2600 processes or converts an electric signalreceived from the outside and provides the processed or convertedelectric signal to the light source module 2200. The power supply part2600 is received in the receiving groove 2719 of the inner case 2700,and is sealed inside the inner case 2700 by the holder 2500. The powersupply part 2600 may include a protrusion 2610, a guide part 2630, abase 2650, and an extension part 2670.

The guide part 2630 has a shape protruding from one side of the base2650 to the outside. The guide part 2630 may be inserted into the holder2500. A plurality of components may be disposed on one surface of thebase 2650. For example, the components may include a DC converter toconvert AC power provided from an external power supply into DC power, adriving chip to control the driving of the light source module 2200, andan electrostatic discharge (ESD) protection device to protect the lightsource module 2200, but the embodiment is not limited thereto.

The extension part 2670 has a shape protruding from an opposite side ofthe base 2650 to the outside. The extension part 2670 is inserted intoan inside of the connection part 2750 of the inner case 2700, andreceives an electric signal from the outside. For example, a width ofthe extension part 2670 may be smaller than or equal to a width of theconnection part 2750 of the inner case 2700. First terminals of a “+electric wire” and a “− electric wire” are electrically connected to theextension part 2670 and second terminals of the “+ electric wire” andthe “− electric wire” may be electrically connected to a socket 2800.

The inner case 2700 may include a molding part therein together with thepower supply part 2600. The molding part is prepared by hardeningmolding liquid, and the power supply part 2600 may be fixed inside theinner case 2700 by the molding part.

The embodiment provides a light emitting device capable of improvinglight extraction efficiency and product yield, a light emitting devicepackage, and a light unit.

A light emitting device according to the embodiment comprises a firstlight emitting structure comprising a first conductive firstsemiconductor layer, a first active layer under the first conductivefirst semiconductor layer, and a second conductive second semiconductorlayer under the first active layer; a second light emitting structurecomprising a first conductive third semiconductor layer, a second activelayer under the first conductive third semiconductor layer, and a secondconductive fourth semiconductor layer under the second active layer; afirst electrode electrically connected to the first conductive firstsemiconductor layer and disposed under the first light emittingstructure; a second electrode electrically connected to the secondconductive second semiconductor layer and disposed under the first lightemitting structure; a third electrode electrically connected to thefirst conductive third semiconductor layer and disposed under the secondlight emitting structure; a fourth electrode electrically connected tothe second conductive fourth semiconductor layer and disposed under thesecond light emitting structure; a first contact portion providedthrough the first light emitting structure and comprising a first regionelectrically connected to the first electrode and a second region makingcontact with a top surface of the first conductive first semiconductorlayer; a second contact portion electrically connected to the second andthird electrodes; and a third contact portion provided through thesecond light emitting structure and comprising a first regionelectrically connected to the third electrode and a second region makingcontact with a top surface of the first conductive third semiconductorlayer.

A light emitting device according to the embodiment comprises a firstlight emitting structure comprising a first conductive firstsemiconductor layer, a first active layer under the first conductivefirst semiconductor layer, and a second conductive second semiconductorlayer under the first active layer; a second light emitting structurecomprising a first conductive third semiconductor layer, a second activelayer under the first conductive third semiconductor layer, and a secondconductive fourth semiconductor layer under the second active layer; afirst electrode electrically connected to the first conductive firstsemiconductor layer and disposed under the first light emittingstructure; a second electrode electrically connected to the secondconductive second semiconductor layer and disposed under the first lightemitting structure; a third electrode electrically connected to thefirst conductive third semiconductor layer and disposed under the secondlight emitting structure; a fourth electrode electrically connected tothe second conductive fourth semiconductor layer and disposed under thesecond light emitting structure; a first contact portion providedthrough the first light emitting structure and comprising a first regionelectrically connected to the first electrode and a second region makingcontact with a top surface of the first conductive first semiconductorlayer; a second contact portion electrically connected to the second andthird electrodes; and a third contact portion provided through thesecond light emitting structure and comprising a first regionelectrically connected to the third electrode and a second region makingcontact with a top surface of the first conductive third semiconductorlayer, wherein a bottom surface of the first contact portion is disposedlower than a bottom surface of the second electrode, and a top surfaceof the first electrode is disposed lower than the bottom surface of thesecond electrode.

A light emitting device according to the embodiment comprises a firstlight emitting structure comprising a first conductive firstsemiconductor layer, a first active layer under the first conductivefirst semiconductor layer, and a second conductive second semiconductorlayer under the first active layer; a second light emitting structurecomprising a first conductive third semiconductor layer, a second activelayer under the first conductive third semiconductor layer, and a secondconductive fourth semiconductor layer under the second active layer; afirst electrode electrically connected to the first conductive firstsemiconductor layer and disposed under the first light emittingstructure; a second electrode electrically connected to the secondconductive second semiconductor layer and disposed under the first lightemitting structure; a third electrode electrically connected to thefirst conductive third semiconductor layer and disposed under the secondlight emitting structure; a fourth electrode electrically connected tothe second conductive fourth semiconductor layer and disposed under thesecond light emitting structure; a first contact portion providedthrough the first light emitting structure and comprising a first regionelectrically connected to the first electrode and a second region makingcontact with a top surface of the first conductive first semiconductorlayer; a second contact portion electrically connected to the second andthird electrodes; and a third contact portion provided through thesecond light emitting structure and comprising a first regionelectrically connected to the third electrode and a second region makingcontact with a top surface of the first conductive third semiconductorlayer, wherein a bottom surface of the first contact portion is arrangedon a same plane with a top surface of the first electrode, and a topsurface of the first electrode is arranged on a same plane with a topsurface of the third electrode.

The light emitting device, the light emitting device package and thelight unit according to the embodiment can improve the light extractionefficiency and product yield.

Any reference in this specification to “one embodiment,” “anembodiment,” “example embodiment,” etc., means that a particularfeature, structure, or characteristic described in connection with theembodiment is included in at least one embodiment of the invention. Theappearances of such phrases in various places in the specification arenot necessarily all referring to the same embodiment. Further, when aparticular feature, structure, or characteristic is described inconnection with any embodiment, it is submitted that it is within thepurview of one skilled in the art to effect such feature, structure, orcharacteristic in connection with other ones of the embodiments.

Although embodiments have been described with reference to a number ofillustrative embodiments thereof, it should be understood that numerousother modifications and embodiments can be devised by those skilled inthe art that will fall within the spirit and scope of the principles ofthis disclosure. More particularly, various variations and modificationsare possible in the component parts and/or arrangements of the subjectcombination arrangement within the scope of the disclosure, the drawingsand the appended claims. In addition to variations and modifications inthe component parts and/or arrangements, alternative uses will also beapparent to those skilled in the art.

What is claimed is:
 1. A light emitting device comprising: a first lightemitting structure having a first conductive first semiconductor layer,a first active layer under the first conductive first semiconductorlayer, and a second conductive second semiconductor layer under thefirst active layer; a second light emitting structure having a firstconductive third semiconductor layer, a second active layer under thefirst conductive third semiconductor layer, and a second conductivefourth semiconductor layer under the second active layer; a firstelectrode electrically connected to the first conductive firstsemiconductor layer and provided under the first light emittingstructure; a second electrode electrically connected to the secondconductive second semiconductor layer and provided under the first lightemitting structure; a third electrode electrically connected to thefirst conductive third semiconductor layer and provided under the secondlight emitting structure; a fourth electrode electrically connected tothe second conductive fourth semiconductor layer and provided under thesecond light emitting structure; a first contact portion providedthrough the first light emitting structure and comprising a first regionelectrically connected to the first electrode and a second region makingcontact with a top surface of the first conductive first semiconductorlayer; a second contact portion electrically connected to the second andthird electrodes; and a third contact portion provided through thesecond light emitting structure and comprising a first regionelectrically connected to the third electrode and a second region makingcontact with a top surface of the first conductive third semiconductorlayer.
 2. The light emitting device of claim 1, further comprising achannel layer exposed at lower peripheral portions of the first andsecond light emitting structures.
 3. The light emitting device of claim1, further comprising a fourth contact portion spaced apart from thesecond light emitting structure and electrically connected to the fourthelectrode.
 4. The light emitting device of claim 1, wherein the firstcontact portion is provided through the first conductive firstsemiconductor layer, the first active layer and the second conductivesecond semiconductor layer.
 5. The light emitting device of claim 1,wherein a bottom surface of the first contact portion is disposed lowerthan a bottom surface of the second electrode.
 6. The light emittingdevice of claim 1, wherein a top surface of the first electrode is lowerthan a bottom surface of the second electrode.
 7. The light emittingdevice of claim 1, wherein the second electrode comprises an ohmiccontact layer and a reflective layer.
 8. The light emitting device ofclaim 1, further comprising a first insulating layer provided in thefirst light emitting structure around the first contact portion.
 9. Thelight emitting device of claim 8, wherein the first insulating layer isprovided through the first conductive first semiconductor layer, thefirst active layer and the second conductive second semiconductor layer.10. The light emitting device of claim 8, further comprising a secondinsulating layer provided under the second conductive secondsemiconductor layer around the first insulating layer.
 11. The lightemitting device of claim 1, further comprising a third insulating layerbetween the first electrode and second electrode.
 12. The light emittingdevice of claim 1, wherein the first contact portion comprises aplurality of first contact portions.
 13. The light emitting device ofclaim 12, wherein the plurality of first contact portions are spacedapart from each other on the top surface of the first conductive firstsemiconductor layer.
 14. The light emitting device of claim 1, whereinthe first electrode comprises a metal layer and a conductive supportmember under the metal layer.
 15. The light emitting device of claim 1,wherein a bottom surface of the first contact portion is arranged on asame plane with a top surface of the first electrode.
 16. The lightemitting device of claim 1, wherein a top surface of the first electrodeis arranged on a same plane with a top surface of the third electrode.17. The light emitting device of claim 1, wherein the second contactportion makes contact with a top surface of the second electrode and atop surface of the third electrode.
 18. A light emitting devicecomprising: a first light emitting structure having a first conductivefirst semiconductor layer, a first active layer under the firstconductive first semiconductor layer, and a second conductive secondsemiconductor layer under the first active layer; a second lightemitting structure having a first conductive third semiconductor layer,a second active layer under the first conductive third semiconductorlayer, and a second conductive fourth semiconductor layer under thesecond active layer; a first electrode electrically connected to thefirst conductive first semiconductor layer and provided under the firstlight emitting structure; a second electrode electrically connected tothe second conductive second semiconductor layer and provided under thefirst light emitting structure; a third electrode electrically connectedto the first conductive third semiconductor layer and provided under thesecond light emitting structure; a fourth electrode electricallyconnected to the second conductive fourth semiconductor layer andprovided under the second light emitting structure; a first contactportion provided through the first light emitting structure andcomprising a first region electrically connected to the first electrodeand a second region making contact with a top surface of the firstconductive first semiconductor layer; a second contact portionelectrically connected to the second and third electrodes; and a thirdcontact portion provided through the second light emitting structure andcomprising a first region electrically connected to the third electrodeand a second region making contact with a top surface of the firstconductive third semiconductor layer, wherein a bottom surface of thefirst contact portion is lower than a bottom surface of the secondelectrode, and a top surface of the first electrode is lower than thebottom surface of the second electrode.
 19. The light emitting device ofclaim 18, wherein the second contact portion makes contact with a topsurface of the second electrode and a top surface of the thirdelectrode.
 20. A light emitting device comprising: a first lightemitting structure including a first conductive first semiconductorlayer, a first active layer under the first conductive firstsemiconductor layer, and a second conductive second semiconductor layerunder the first active layer; a second light emitting structureincluding a first conductive third semiconductor layer, a second activelayer under the first conductive third semiconductor layer, and a secondconductive fourth semiconductor layer under the second active layer; afirst electrode electrically connected to the first conductive firstsemiconductor layer and provided under the first light emittingstructure; a second electrode electrically connected to the secondconductive second semiconductor layer and provided under the first lightemitting structure; a third electrode electrically connected to thefirst conductive third semiconductor layer and provided under the secondlight emitting structure; a fourth electrode electrically connected tothe second conductive fourth semiconductor layer and provided under thesecond light emitting structure; a first contact portion providedthrough the first light emitting structure and comprising a first regionelectrically connected to the first electrode and a second region makingcontact with a top surface of the first conductive first semiconductorlayer; a second contact portion electrically connected to the second andthird electrodes; and a third contact portion provided through thesecond light emitting structure and comprising a first regionelectrically connected to the third electrode and a second region makingcontact with a top surface of the first conductive third semiconductorlayer, wherein a bottom surface of the first contact portion is arrangedon a same plane with a top surface of the first electrode, and a topsurface of the first electrode is arranged on a same plane with a topsurface of the third electrode.